Transfer method

ABSTRACT

A rail-guided transfer system, capable of preventing the reduction of the operation rate of manufacturing equipments on a manufacturing line such as a semiconductor manufacturing line etc., is provided. Two RGVs  11 A and  11 B are arranged in advance on one transfer rail  3  laid between two stockers BS 1  and BS 2.  For example, when maintenance of the manufacturing equipment EQ 8  provided between the stockers BS 1  and BS 2  is done, a transfer region MA 1  of the RGV  11 A is set from the stocker BS 1  to the manufacturing equipment EQ 7  and a transfer region MA 2  of the RGV  11 B is set from the stocker BS 2  to the manufacturing equipment EQ 9.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a transfer technology and, more specifically, to a technique effectively applied to a rail-guided transfer system.

[0002] For example, in a semiconductor manufacturing line, with the increase of the diameters of semiconductor wafers (hereinafter “wafer”), the weight per one wafer has been increasing. Therefore, the mechanical automation of the wafer transfer has been developed.

[0003] For example, as described in “Monthly Semiconductor World” pages 131 to 149 issued on Dec. 20, 1997 by press journal Inc., the various manufacturing equipments (including test equipments) are divided into the equipment groups called bay, and arranged in the clean room by the bay, in the semiconductor manufacturing line adapted to the wafer with a diameter of 300 mm. Therefore, as corresponding to such division, the automated wafer transfer system also comprises individual components such as a bay-to-bay transfer, an in-bay transfer, and a stocker.

[0004] Of these components, the bay-to-bay transfer uses the overhead transfer method generally called an OHS (Over Head Shuttle). Also, the in-bay transfer uses: the transfer vehicle called a RGV (Rail-Guided Vehicle) automatically moving on a rail; the transfer vehicle called an AGV (Automatic Guided Vehicle) automatically moving without a guide rail; an OHT (Over-head Hoist Transport) which is one of the overhead transfer methods; or the like.

[0005] For example, the gazette of Japanese Patent Laid-Open No. 8-153767 discloses a technique for improving a transfer processing capability, in which: two substrate transfer robots, capable of moving on a rail, are arranged on one rail; the region in which each substrate transfer robot is activated is set; and substrates such as a wafer, a color filter substrate, a thermal head substrate, and a printed board, etc. are transferred between a plurality of substrate processing equipments.

SUMMARY OF THE INVENTION

[0006] The inventors have examined the rail-guided transfer system using the RGVs. Since the RGVs move on a track such as rails or the like, more stable movement can be achieved in comparison with the AGV moving without the guide rail. Therefore, it is possible to easily control the movement thereof. The inventors have found out the following problems in the rail-guided transfer system using such RGV.

[0007] That is, in the rail-guided transfer system using the RGV, one RGV is usually installed on a single rail for the purpose of avoiding complicating the layout of the transfer system and the system configuration (control) and avoiding the increase of the cost to provide the transfer system. However, when unusual operations, such as maintenance, additional installation, and new installation, etc. of the manufacturing equipments (including test equipments), are required in the manufacturing line, for example, in the semiconductor manufacturing line and if operators must move into the manufacturing equipment side from the single rail side, it is necessary to block off the transfer path at the position where the required unusual operations have occured in order to ensure the safety of the operators and it is necessary for the RGV not to reach the position where the required unusual operations have occured. Therefore, under the condition that the transfer path is blocked off, the RGV can operate only in one side of a manufacturing equipment group because it cannot move beyond the border of the position where the required unusual operations have occurred. As a result, such a problem arises that the operation rate of the manufacturing equipment is lowered.

[0008] An object of the present invention is to provide a rail-guided transfer system capable of preventing the reduction of the operation rates of the manufacturing equipments in a manufacturing line such as a semiconductor manufacturing line.

[0009] The above and other objects and novel characteristics of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0010] The typical ones of the inventions disclosed in this application will be briefly described as follows.

[0011] That is, the present invention is a transfer method comprising the steps of: using a single track connecting a plurality of manufacturing equipments, and a plurality of transfer means operating along said single track; and transferring, to said manufacturing equipments, an object to be transferred, wherein:

[0012] (a) each of said transfer means has a transfer mode of a first step and a second step after said first step; and

[0013] (b) a first transfer region of each of said transfer means at said first step and a second transfer region of each of said second transfer means at said second step are different from each other in range.

[0014] Also, the present invention is a transfer method comprising the steps of: using a single track connecting a plurality of manufacturing equipments, and a plurality of transfer means operating along said single track; and transferring, to said manufacturing equipments, an object to be transferred, wherein:

[0015] (a) each of said transfer means has a transfer mode of a first step and a second step at the time of blocking off said single track; and

[0016] (b) a first transfer region of each of said transfer means at said first step and a second transfer region of each of said transfer means at said second step are different from each other in range.

[0017] Also, the present invention is a transfer method comprising the steps of: using a single track connecting a plurality of manufacturing equipments, and a plurality of transfer means operating along said single track; and transferring, to said manufacturing equipments, an object to be transferred, wherein:

[0018] (a) each of said transfer means has a transfer mode of a first step being at which a difference in operation rate occurs between said plurality of transfer means and a second step other than said first step; and

[0019] (b) a first transfer region of each of said transfer means at said first step and a second transfer region of each of said transfer means at said second step are different from each other in range.

[0020] Also, the present invention is a transfer method comprising the steps of: using a single track connecting a plurality of manufacturing equipments, and a plurality of transfer means operating along said single track; and transferring, to said manufacturing equipments, an object to be transferred, wherein:

[0021] (a) each of said transfer means has a transfer mode of a first step at which there occurs a difference in the standby time until said object to be transferred is transferred to said plurality of manufacturing equipments and a second step other than said first step; and

[0022] (b) a first transfer region of each of said transfer means at said first step and a second transfer region of each of said transfer means at said second step are different from each other in range.

[0023] Further, said first transfer region and said second transfer region of each of said plurality of transfer means, are mutually separated from said first transfer region and said second transfer region of the other of said transfer means.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024]FIG. 1 is an entire plan view showing the full-automated wafer transfer system of a semiconductor manufacturing line according to a first embodiment of the present invention;

[0025]FIG. 2 is a plan view of a part of the full-automated wafer transfer system shown in FIG. 1;

[0026]FIG. 3 is a plan view showing the case where manufacturing equipments are newly or additionally installed in a part of the full-automated wafer transfer system shown in FIG. 1;

[0027]FIG. 4 is a plan view showing the case where manufacturing equipments are newly or additionally installed in a part of the full-automated wafer transfer system shown in FIG. 1;

[0028]FIG. 5 is a plan view showing the case where the maintenance of the manufacturing equipments is done in a part of the full-automated wafer transfer system shown in FIG. 1;

[0029]FIG. 6 is a plan view showing a part of the full-automated wafer transfer system of the semiconductor manufacturing line according to a second embodiment of the present invention;

[0030]FIG. 7 is an entire plan view showing the full-automated wafer transfer system of the semiconductor manufacturing line according to a third embodiment of the present invention;

[0031]FIG. 8 is a plan view of a part of the full-automated wafer transfer system shown in FIG. 7;

[0032]FIG. 9 is a plan view showing the case where manufacturing equipments are newly or additionally installed in a part of the full-automated wafer transfer system shown in FIG. 7;

[0033]FIG. 10 is a plan view showing the case where manufacturing equipments are newly or additionally installed in a part of the full-automated wafer transfer system shown in FIG. 7;

[0034]FIG. 11 is a plan view showing the case where the maintenance of the manufacturing equipments is done in a part of the full-automated wafer transfer system shown in FIG. 7; and

[0035]FIG. 12 is a plan view showing a part of the full-automated wafer transfer system of the semiconductor manufacturing line according to a fourth embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that components having the same function are denoted by the same reference symbols throughout all of the drawings for describing the embodiments, and the repetitive description thereof will be omitted.

[0037] (First Embodiment)

[0038]FIG. 1 is an entire plan view showing a full-automated wafer transfer system, which includes the semiconductor manufacturing lines adapted to the wafer with a diameter of, for example, 300 mm.

[0039] Various manufacturing equipments EQ (including test equipments), such as a thermal treatment equipment, an ion implantation equipment, an etching equipment, a film-forming equipment, a cleaning equipment, a photoresist coating equipment, and a exposure equipment, etc. used in the semiconductor manufacture, are divided into several bays (equipment groups) and arranged in a clean room CR. These manufacturing equipments EQ are used for processing the wafer. Also, the full-automated wafer transfer system in the clean room CR corresponds to arrangement of them and comprises a plurality of transfer systems and stockers BS connected between the transfer systems.

[0040] A wafer lot (object to be transferred) between the respective stockers is transferred by each of the transfer systems provided in the clean room CR. Meanwhile, the wafer lot relative to the manufacturing equipment is transferred by a RGV (Rail-Guided Vehicle) (transfer means) 11, which runs on a transfer rail (single track) 3 laid in the clean room CR. More specifically, the transfer systems of the first embodiment are rail-guided transfer systems. In this embodiment, the lot means a group of wafers that are manufactured under the same condition and to which various treatments are performed (or have been performed) under the same condition. The transfer rail 3 is used commonly by two RGVs 11. The operational state of the RGV 11 is controlled by an operation control system (not shown) electrically connected to the RGV 11.

[0041]FIG. 2 is a plan view of a part of the transfer systems shown in FIG. 1.

[0042] One transfer rail 3 is laid between the two stockers BS1 and BS2, and the two RGVs 11A and 11B are provided on the transfer rail 3. Also, for example, n manufacturing equipments EQ1 to EQn (n>9) are provided between the stockers BS1 and BS2.

[0043] As a first step, transfer regions (first transfer regions) MA 1 and MA2, in which the RGVs 11A and 11B can move, are respectively set in the first embodiment. This setting of the transfer regions MA1 and MA2 is performed by the above-mentioned operation control system. At this time, if the manufacturing equipment EQ6 is laid in both the transfer regions MA1 and MA2 and when the wafer lot is carried from the RGV 11A into the manufacturing equipment EQ6, the RGV 11A stays in front of the manufacturing equipment EQ6. In such a situation, even if the RGV 11B holds the wafer lot to be carried into the manufacturing equipment EQ6, the RGV 11B cannot move to the manufacturing equipment EQ6 since the RGV 11A stays in front of the manufacturing equipment EQ6. More specifically, since the wafer lot, which the RGV 11B holds, cannot be carried into the manufacturing equipment EQ6, the transfer efficiency of the RGV 11B is lowered. For its prevention, in the first embodiment, the transfer regions MA1 and MA2 are set so that one part or the entire of them may not be overlapped. The transfer system shown in FIG. 2 illustrates the example in which the transfer region MA1 is a range of the stocker BS1 to the manufacturing equipment EQ5 and the transfer region MA2 is a range of the manufacturing equipment EQ6 to the stocker BS2. Therefore, the reduction of the transfer efficiency due to the mutual interference of the two RGV 11A and 11B can be prevented.

[0044] Additionally, when there is the wafer lot to be carried from the stocker BS1 in the transfer region MA1 to one of the manufacturing equipments EQ6 to EQn in the transfer region MA2, the lot is transferred from the stocker BS1 to the stocker BS2 by the other transfer systems and thereafter can be transferred by the RGV 11B from the stocker BS2 to the desired manufacturing equipment in the transfer region MA2.

[0045] Note that, if the step of transferring the wafer lot by the RGVs 11A and 11B can be controlled without reducing the transfer efficiency of the RGVs 11A and 11B and without interfering the mutual movement of the RGVs 11A and 11B, then the transfer regions MA1 and MA2 may be set so that one part or the entire of them is overlapped. In such a case, since the transfer path of the lot is not determined to a single path, it is possible to appropriately select the transfer path according to circumstances.

[0046]FIGS. 3 and 4 are plan views showing the case where manufacturing equipments different from the manufacturing equipments EQ1 to EQn are newly provided between the stockers BS1 and BS2 or the case where manufacturing equipments of the same type as any of the manufacturing equipments EQ1 to EQn are additionally provided between the stockers BS1 and BS2.

[0047] As shown in FIG. 3, for example, when the manufacturing equipments different from the manufacturing equipments EQ1 to EQn are newly provided between the stockers BS1 and BS2 or when the manufacturing equipments of the same type as any of the manufacturing equipments EQ1 to EQn are additionally provided between the stockers BS1 and BS2 (second step), they are sequentially installed from the positions close to the stockers BS1 and BS2. For example, when the manufacturing equipments EQ4 to EQ7 are to be installed in the region (first region) between the manufacturing equipments EQ3 and EQ8 under the condition that the manufacturing equipments EQ1 to EQ3 are provided at the position close to the stocker BS1 and the manufacturing equipments EQ8 to EQn are provided at the position close to the stocker BS2, the manufacturing equipments EQ4 to EQ7 are sequentially installed from the positions close to the manufacturing equipments EQ3 and EQ8 and the transfer regions MA1 and MA2 of the RGVs 11A and 11B are sequentially expanded in accordance with the newly installed manufacturing equipments. In this manner, the new transfer regions (second transfer regions) MA1 and MA2 are sequentially set. Consequently, it becomes possible to carry sequentially the wafer lots into the newly installed manufacturing equipments EQ4 to EQ7.

[0048] Also, as shown in FIG. 4, when manufacturing equipments different from the manufacturing equipments EQ1 to EQn are newly provided between the stockers BS1 and BS2 or when manufacturing equipments of the same type as any of the manufacturing equipment EQ1 to EQn are additionally provided between the stockers BS1 and BS2 (second step), the manufacturing equipments EQ4 to EQ7 may be sequentially installed from the position close to the stocker BS1 toward the stocker BS2. For example, when the manufacturing equipments EQ4 to EQ7 are installed in the region (first region) between the manufacturing equipments EQ3 and EQ8 under the condition that the manufacturing equipments EQ1 to EQ3 are provided at the position close to the stocker BS1 and the manufacturing equipments EQ8 to EQn are provided at the position close to the stocker BS2, the manufacturing equipments EQ4 to EQ7 are sequentially installed from that close to the manufacturing equipment EQ3 and the transfer region MA1 of the RGV 11A is accordingly expanded sequentially up to the newly installed manufacturing equipments. In this manner, the new transfer region (second transfer region) MA1 is sequentially set. Consequently, the wafer lots can be carried into the newly installed manufacturing equipments EQ4 to EQ7.

[0049] When the manufacturing equipments are installed in the manner as mentioned above, the transfer rail 3 is blocked off so that the RGV cannot enter into the region in which the process of installing the manufacturing equipments is performed, in order to ensure the safety of operators, for example, by taking into consideration the operators come from the side of transfer rail 3 into the region in which the manufacturing equipments are installed. At this time, if only one RGV is provided on the transfer rail 3, the transfer by the RGV can be made only in one of the transfer regions MA1 and MA2. Therefore, the wafer lot cannot be carried into the manufacturing equipments arranged in the other of the transfer regions MA1 and MA2 in which the transfer by the RGV cannot be made, and thus there is concern about the problem of reducing the operation rate of the manufacturing equipments. Meanwhile, according to the installation method of the manufacturing equipments and the expansion method of the transfer regions MA1 and MA2 in the first embodiment as described with reference to FIGS. 3 and 4, the RGVs 11A and RGV 11B are in advance provided in the transfer regions MA1 and MA2, respectively. Therefore, it is possible to prevent the occurrence of the problem that the wafer lot cannot be carried into the manufacturing equipments arranged in one of the transfer regions MA1 and MA2 and thereby the operation rate of the manufacturing equipment is reduced. As a result, it is possible to prevent the increase in TAT of the products manufactured in the semiconductor manufacturing line according to the first embodiment.

[0050]FIG. 5 is a plan view showing the case where maintenance, including checks and repair, etc. of any of the manufacturing equipments EQ1 to EQn provided between the stockers BS1 and BS2, is done.

[0051] Also, even in the case of doing the maintenance of any of the manufacturing equipments EQ1 to EQn provided between the stockers BS1 and BS2, the transfer rail 3 is blocked off so that the RGV cannot enter into the region, in which the maintenance of the manufacturing equipments is done, in order to ensure the safety of the operators, for example, by taking into consideration the operators come from the side of the transfer rail 3 toward the manufacturing equipment of which the maintenance is done. Also in such a condition, if only one RGV is provided on the transfer rail 3, the transfer by the RGV can be made only in one of the transfer regions MA1 and MA2. Accordingly, the wafer lot cannot be carried into the manufacturing equipments arranged in the other of the transfer regions MA1 and MA2, in which the transfer operation by the RGV cannot be performed, and thus there is concern about the problem of reducing the operation rate of the manufacturing equipment.

[0052] Therefore, in the first embodiment, as shown in FIG. 5, when doing the maintenance of, for example, the manufacturing equipment EQ8 provided in the region (first region) between the manufacturing equipments EQ7 and EQ9 (second step), the transfer region (first transfer region) MA1 of the RGV 11A is set from the stocker BS1 to the manufacturing equipment EQ7 and the transfer region (second transfer region) MA2 of the RGV 11B is set from the stocker BS2 to the manufacturing equipment EQ9, by making use of the two RGVs 11A and 11B arranged in advance on the transfer rail 3. Due to this manner, it becomes possible to prevent the occurrence of the problem that the wafer lot cannot be carried into the manufacturing equipments arranged in one of the transfer regions MA1 and MA2 and thereby the operation rate of the manufacturing equipment is reduced. As a result, it is possible to prevent the increase in TAT of the products manufactured in the semiconductor manufacturing line according to the first embodiment.

[0053] (Second Embodiment)

[0054] Next, the full-automated wafer transfer system according to a second embodiment will be described.

[0055] As shown in FIG. 6, in the transfer system in the full-automated wafer transfer system according to the second embodiment, similarly to the first embodiment, one transfer rail 3 is laid between the two stockers BS1 and BS2, and the two RGVs 11A and 11B are arranged on the transfer rail 3. Additionally, for example, n (n>9) manufacturing equipments EQ1 to EQn (including test equipments) are provided between the stockers BS1 and BS2.

[0056] The second embodiment is intended to achieve the equalization of the operation rates of the RGVs 11A and 11B and the operation rates of the manufacturing equipments EQ1 to EQn. In this embodiment, the operation rates of the RGVs 11A and 11B indicate the rate of the actually operated time of the RGVs 11A and 11B (serviced time) with respect to the operating time of the transfer system (serviceable time), and the operation rates of the manufacturing equipments EQ1 to EQn indicate the rate of the actually processed time of the manufacturing equipments EQ1 to EQn with respect to the processing possible time of the manufacturing equipments.

[0057] Also in the second embodiment, as the first step similarly to the first embodiment, the transfer regions (first transfer regions) MA1 and MA2, on which the RGVs 11A and 12A can respectively move, are set and then the transfer system is activated. At this time, if the difference occurs between the operation rates of the RGVs 11A and 11B by, for example, setting the transfer region MA1 from the stocker BS1 to the manufacturing equipment EQ8 and the transfer region MA2 from the stocker BS2 to the manufacturing equipment EQ9, then there is concern about the occurrence of the difference between the lot standby time of the manufacturing equipments included in the transfer region MA1 and that of the manufacturing equipments included in the transfer region MA2. In this case, since the operation rate is lowered in the manufacturing equipment in which the lot standby time is increased, there is concern about the increase in the TAT of the products manufactured in the semiconductor manufacturing line according to the second embodiment.

[0058] For its solution, in the second embodiment, when there has occured the difference between the operation rates of the RGVs 11A and 11B, for example, when the operation rate of the RGV 11A is about 70% and that of the RGV 11B is about 50%, the transfer regions MA1 and MA2 are respectively expanded or reduced so as to equalize the operation rates of the RGVs 11A and 11B (for example, about 60%), whereby the new transfer regions (second transfer regions) MA1 and MA2 are set (second step). For example, if the operation rates of the RGVs 11A and 11 b are nearly the same by, for example, reducing the transfer region MA1 from the stocker BS1 to the manufacturing equipment EQ5 and expanding the transfer region MA2 from the stocker BS2 to the manufacturing equipment EQ6, then such situation may be set. In this manner, it is possible to reduce the difference between the lot standby time of the manufacturing equipments EQ1 to EQ5 included in the transfer region MA1 and that of the manufacturing equipments EQ6 to EQn included in the transfer region MA2. As a result, since the operation rates of the manufacturing equipments EQ1 to EQn can be equalized, it is possible to prevent the increase in TAT of the products manufactured in the semiconductor manufacturing line according to the second embodiment. More specifically, since it is possible to reduce the lot standby time of the manufacturing equipments EQ1 to EQn by setting the transfer regions MA1 and MA2 based on the processing time (time required for the process performed to the wafer), the frequency of the processing, and the timing of the processing (variation in the frequency of the processing) of each of the manufacturing equipments EQ1 to EQn, then it is possible to reduce the TAT of the products manufactured in the semiconductor manufacturing line according to the second embodiment.

[0059] (Third Embodiment)

[0060]FIG. 7 is an entire plan view of a full-automated wafer transfer system of semiconductor manufacturing lines according to a third embodiment.

[0061] Also in a third embodiment, similarly to the first embodiment, the various manufacturing equipments EQ (including test equipments) are divided into a plurality of bays (equipment group) and arranged in the clean room CR. Also, the wafer lot is transferred between the respective stockers by transfer systems provided in the clean room CR. The transfer of the wafer lot relative to the manufacturing equipments is done by the RGV 11 running on the transfer rail 3 laid on the floor of the clean room CR. However, in the third embodiment, three stockers BS are connected by one transfer rail 3, and the one transfer rail 3 is commonly used by the three RGVs 11.

[0062]FIG. 8 is a plan view of a part of the full-automated wafer transfer systems shown in FIG. 7.

[0063] As shown in FIG. 8, the one transfer rail 3 is laid so as to connect the three stockers BS1, BS2 and BS3, and the three RGVs 11A, 11B and 11C are provided on the transfer rail 3. Further, n (n>7) manufacturing equipments EQ1A to EQnA are arranged between the stockers BS1 and BS2, and n (n>7) manufacturing equipments EQ1B to EQnB are arranged between the stockers BS2 and BS3.

[0064] Also in the third embodiment, as a first step similarly to the first embodiment, the transfer regions (first transfer region) MA1, MA2 and MA3, in which the RGVs 11A, 11B and 11C can respectively move, are set. At this time, for example, in the case where the manufacturing equipment EQ4A is laid in both the transfer regions MA1 and MA2, the RGV 11A stays in front of the manufacturing equipment EQ4A when the wafer lot is carried from the RGV 11A into the manufacturing equipment EQ4A. In such a situation, even if the RGV 11B holds the wafer lot to be carried into the manufacturing equipment EQ4A, the RGV 11B cannot move to the manufacturing equipment EQ4A because the RGV 11A stays in front of the manufacturing equipment EQ4A. More specifically, since the wafer lot held by the RGV 11B cannot be carried into the manufacturing equipment EQ4A, the transfer efficiency of the RGV 11B is lowered. Also, for example, the same problem occurs in the case where the manufacturing equipment EQ4B is laid in both the transfer regions MA2 and MA3. For its prevention, the transfer regions MA1, MA2 and MA3 in the third embodiment are set so that a part or the entire of them cannot be overlapped. The transfer system shown in FIG. 8 illustrates the example in which the transfer region MA1 ranges from the stocker BS1 to the manufacturing equipment EQ4A and the transfer region MA2 ranges from the manufacturing equipment EQ5A to the manufacturing equipment EQ4B and the transfer region MA3 ranges from the manufacturing equipment EQ5B to the stocker BS3. Therefore, the reduction of the transfer efficiency, due to the interference of the three RGVs 11A, 11B and 11C with the mutual move, can be prevented.

[0065] Also, similarly to the first embodiment, for example, when there is the wafer lot to be carried from the stocker BS1 arranged in the transfer region MA1 to one of the manufacturing equipments EQ5A to EQ4B arranged in the transfer region MA2, the lot is transferred from the stocker BS1 to the stocker BS2 by the other transfer system, and then it is transferred from the stocker BS2 to the desired manufacturing equipment arranged in the transfer region MA2 by the RGV 11B. Additionally, the same method can be applied in the case where there is the wafer lot to be carried from the stocker BS1 to one of the manufacturing equipments EQ5B to EQnB arranged in the transfer region MA3, and in the case of doing the transfer from the stocker BS2 to the other transfer regions and in the case of doing the transfer from the stocker BS3 to the other transfer regions.

[0066] Note that, also in the third embodiment, if the transfer of the wafer lot by the RGVs 11A, 11B and 11C can be controlled without reducing the transfer efficiency of the RGVs 11A, 11B and 11C and without interfering with the mutual movement of the RGVs 11A, 11B and 11C, then the transfer regions MA1, MA2 and MA3 may be set so that each part or the entire of them is overlapped. In such a case, since the transfer path of the lot is not determined to a single path, it is possible to appropriately select the transfer path according to circumstances.

[0067]FIGS. 9 and 10 are plan views showing the case where manufacturing equipments different from the manufacturing equipments EQ1A to EQnA and EQ1B to EQnB are newly provided between the stockers BS1 and BS2 and between the stockers BS2 and BS3 or the case where manufacturing equipments of the same type as any of the manufacturing equipments EQ1A to EQnA and EQ1B to EQnB are additionally provided between the stockers BS1 and BS2 and between the stockers BS2 and BS3.

[0068] As shown in FIG. 9, when the manufacturing equipments different from the manufacturing equipments EQ1A to EQnA and EQ1B to EQnB are newly provided between the stockers BS1 and BS2 or when the manufacturing equipments of the same type as any of the manufacturing equipments EQ1A to EQnA and EQ1B to EQnB are additionally provided between the stockers BS1 and BS2 (second step), similarly to the first embodiment described with reference to FIG. 3 the different manufacturing equipments are sequentially installed from the positions close to the stockers BS1 and BS2. Similarly, when the manufacturing equipments different from the manufacturing equipments EQ1A to EQnA and EQ1B to EQnB are newly provided between the stockers BS2 and BS3 or when the manufacturing equipments of the same type as any of the manufacturing equipments EQ1A to EQnA and EQ1B to EQnB are additionally provided between the stockers BS2 and BS3, the different manufacturing equipments are sequentially installed from the positions close to the stockers BS2 and BS3. For example, it is assumed that the manufacturing equipments EQ1A and EQ2A are provided at the position close to the stocker BS1 and the manufacturing equipments EQ7A to EQnA are provided at the position close to the stocker BS2 between the stockers BS1 and BS2, and that the manufacturing equipments EQ1B and EQ2B are provided at the position close to the stocker BS2 and the manufacturing equipments EQ7B to EQnB are provided at the position close to the stocker BS3 between the stockers BS2 and BS3. In this case, when the manufacturing equipments EQ3A to EQ6A are to be installed in the region (first region) between the manufacturing equipments EQ2A and EQ7A, the manufacturing equipments EQ3A to EQ6A are sequentially installed from the positions close to the manufacturing equipments EQ2A and EQ7A and the respective transfer regions MA1 and MA2 of the RGVs 11A and 11B are accordingly expanded sequentially up to the newly installed manufacturing equipments. Similarly, when the manufacturing equipments EQ3B to EQ6B are to be installed in the region (first region) between the manufacturing equipments EQ2B and EQ7B, the manufacturing equipments EQ3B to EQ6B are sequentially installed from the positions close to the manufacturing equipments EQ2B and EQ7B and the respective transfer regions MA2 and MA3 of the RGVs 11B and 11C are accordingly expanded sequentially up to the newly installed manufacturing equipments. In this manner, the new transfer regions (second transfer regions) MA1, MA2 and MA3 are sequentially set. Consequently, the wafer lots can be carried into the newly installed manufacturing equipments EQ3A to EQ6A and EQ3B to EQ6B.

[0069] Alternatively, as shown in FIG. 10, it is also possible to sequentially install the manufacturing equipments EQ3A to EQ6A from the position close to the stocker BS1 toward the stocker BS2 and to accordingly expand the transfer region MA1 of the RGV 11A up to the newly installed manufacturing equipments, thereby making it possible to carry the wafer lot into the newly installed manufacturing equipments EQ3A to EQ6A. Similarly, it is also possible to sequentially install the manufacturing equipments EQ3B to EQ6B from that close to the stocker BS2 toward the stocker BS3 and to accordingly expand the transfer region MA2 of the RGV 11B up to the newly installed manufacturing equipments, thereby making it possible to carry the wafer lot into the newly installed manufacturing equipments EQ3B to EQ6B.

[0070] As described in the first embodiment, since the transfer rail 3 is blocked off so that the RGV cannot enter into the region in which the installation of the manufacturing equipments are performed, the transfer operation by the RGV cannot be done only in one of the transfer regions MA1, MA2 and MA3 if only one RGV is provided on the transfer rail 3. Meanwhile, according to the installation method of the manufacturing equipment and the expansion method of the transfer regions MA1, MA2 and MA3 in the third embodiment described with reference to FIGS. 9 and 10, the RGVs 11A, 11B and 11C are in advance provided in the transfer regions MA1, MA2 and MA3, respectively. Therefore, it is possible to prevent the occurrence of the problem that the wafer lot cannot be carried into the manufacturing equipments arranged in two of the transfer regions MA1, MA2 and MA3 and thereby the operation rate of the manufacturing equipment is reduced. As a result, it is possible to prevent the increase in TAT of the products manufactured in the semiconductor manufacturing line according to the third embodiment.

[0071] Also, as described above, since the three RGVs are arranged on the transfer rail 3 and the stockers of the same number as the RGVs are arranged in the region along the transfer rail 3, the transfer region corresponding to each RGV in more detail can be set in comparison with the case as described in the first embodiment in which the two RGVs are provided and the stockers of the same number as the RGVs are arranged (see FIGS. 3 and 4). In this manner, according to the third embodiment, the transfer region corresponding to each RGV can be set in more detail and in accordance with its use in comparison with the above first embodiment. For example, when installing the manufacturing equipments in the semiconductor manufacturing line, the transfer area of the RGV in accordance with the layout of the manufacturing equipments can be set more easily than the first embodiment.

[0072] Meanwhile, in the third embodiment, the example, in which the three RGVs are arranged on the transfer rail 3 and the stockers of the same number as the RGVs are arranged in the region along the transfer rail 3, has been described. However, the number of the RGVs is not limited to three, and the further more number of RGVs may be arranged or a method for arranging the number of stockers proportional to the number of the RGVs may be used. By so doing, since a transfer region corresponding to each RGV can be set in further detail, the transfer area is set in accordance with its use more easily.

[0073]FIG. 11 is a plan view showing the case where the maintenance including a check or repair is done for two of the manufacturing equipments EQ1A to EQnA and EQ1B to EQnB provided between the stockers BS1 and BS3.

[0074] Similarly to the first embodiment, also in the case where the maintenance is done for two of the manufacturing equipments EQ1A to EQnA and EQ1B to EQnB provided between the stockers BS1 and BS3, the transfer rail 3 is blocked off so that the RGV cannot enter into the region in which the maintenance of the manufacturing equipments is done. Also in such a situation, if only one RGV is arranged on the transfer rail 3, the transfer operation by the RGV cannot be performed in only one region of the transfer regions MA1, MA2 and MA3. Therefore, the wafer lot is not carried into the manufacturing equipments arranged in the other two transfer regions in which the transfer operation by the RGV cannot be performed, whereby there occurs concern about the problem that the operation rate of the manufacturing equipment is lowered.

[0075] Therefore, in the third embodiment, as shown in FIG. 11, when the maintenance is done (second step) for the manufacturing equipment EQ6A provided in the region (first region) between the manufacturing equipments EQ5A and EQ7A and for the manufacturing equipment EQ6B provided in the region (first region) between the manufacturing equipments EQ5B and EQ7B, the three RGVs 11A, 11B and 11C arranged in advance on the transfer rail 3 are utilized. More specifically, the transfer region (second transfer region) MA1 of the RGV 11A is set from the stocker BS1 to the manufacturing equipment EQ5A, the transfer region (second transfer region) MA2 of the RGV 11B is set from the manufacturing equipment EQ7A to the manufacturing equipment EQ5B, and the transfer region (second transfer region) MA3 of the RGV 11C is set from the manufacturing equipment EQ7B to the stocker BS3. By so doing, it becomes possible to prevent the occurrence of the problem that the wafer lot is not carried into the manufacturing equipments arranged in two of the transfer regions MA1, MA2 and MA3 and thereby the operation rate of the manufacturing equipment is reduced. As a result, it is possible to prevent the increase in TAT of the products manufactured in the semiconductor manufacturing line according to the third embodiment.

[0076] As described above, the wafer lots can be carried without reducing the operation rates of the manufacturing equipments by arranging the three RGVs on the transfer rail 3 and providing the stockers of the same number as the RGVs in the region being along the transfer rail 3 even when the maintenance is done for two of the manufacturing equipments provided along the transfer rail 3. Additionally, by not limiting the number of the RGVs to three, by arranging the further more number of RGVs, and also by arranging the number of stockers proportional to the further more number, it becomes possible to transfer the wafer lots without reducing the operation rates of the manufacturing equipments even when the maintenance is done for two or more manufacturing equipments.

[0077] The same effect as that of the first embodiment can be achieved in the third embodiment as described above.

[0078] (Fourth Embodiment)

[0079] Next, a transfer system in a full-automated wafer transfer system according to a fourth embodiment will be described.

[0080] As shown in FIG. 12, in the transfer system in the full-automated wafer transfer system according to a fourth embodiment, similarly to that in the third embodiment, one transfer rail 3 connecting three stockers BS1, BS2 and BS3 is laid and three RGVs 11A, 11B and 11C are arranged on the transfer rail 3. Further, for example, n (n>7) manufacturing equipments EQ1A to EQnA (including test equipments) are arranged between the stockers BS1 and BS2, and n (n>7) manufacturing equipments EQ1B to EQnB (including test equipments) are arranged between the stockers BS2 and BS3.

[0081] Similarly to the above-mentioned second embodiment, the fourth embodiment is intended to achieve the equalization of the operation rates of the RGVs 11A, 11B and 11C. It is also intended to achieve the equalization of the operation rates of the manufacturing equipments EQ1A to EQnA and EQ1B to EQnB.

[0082] Also in the fourth embodiment, as a first step similarly to the above-mentioned third embodiment, the transfer regions (first transfer regions) MA1, MA2 and MA3, in which the RGVs 11A, 11B and 11C are moved, are set and then the operation of the transfer system is started. At this time, for example, if the difference in operation rate between the RGVs 11A, 11B, and 11C occurs by: setting the transfer region MA1 from the stocker BS1 to the manufacturing equipment EQ4A; setting the transfer ration MA2 from the manufacturing equipment EQ5A to the manufacturing equipment EQ4B; and setting the transfer region MA3 from the stocker BS3 to the manufacturing equipment EQ5B, then there is concern about the occurrence of the difference between the lot standby time of the manufacturing equipments included in the transfer region MA1, that of the manufacturing equipments included in the transfer region MA2, and that of the manufacturing equipments included in the transfer region MA3. In such a case, since the operation rate of the manufacturing equipment, in which the lot standby time is increased, is lowered, there is concern about the increase in the TAT of the products manufactured in the semiconductor manufacturing line in the fourth embodiment.

[0083] For its solution, in the fourth embodiment, when the difference in operation rate between the RGVs 11A, 11B, and 11C occurs, for example, when the operation rate of the RGV 11A is about 40% and that of the RGV 11B is about 60% and that of the RGV 11C is about 80%, the transfer regions MA1, MA2 and MA3 are respectively expanded or reduced so as to make the operation rates of the RGV 11A, 11B and 11C uniform (for example, about 60%), whereby the new transfer regions (second transfer regions) MA1, MA2 and MA3 are set (second step). For example, the transfer region MA1 is expanded from the stocker BS1 to the manufacturing equipment EQ6A, the transfer region MA2 is changed from the manufacturing equipment EQ7A to the manufacturing equipment EQ6B, and the transfer region MA3 is reduced from the stocker BS2 to the manufacturing equipment EQ7B. By so doing, if the operation rates of the RGVs 11A, 11B, and 11C are nearly the same, the above situation is set. Thereby, it is possible to reduce the difference between the lot standby time of the manufacturing equipments EQ1A to EQ6A included in the transfer region MA1, that of the manufacturing equipments EQ7A to EQ6B included in the transfer region MA2, and that of the manufacturing equipments EQ7B to EQNB included in the transfer region MA3. As a result, it is possible to equalize the operation rates of the manufacturing equipments EQ1A to EQnA and those of the manufacturing equipments EQ1B to EqnB, and therefore to prevent the increase in TAT of the products manufactured in the semiconductor manufacturing line in the fourth embodiment. More specifically, similarly to the above-mentioned second embodiment, by setting the transfer regions MA1, MA2 and MA3 based on the processing time, the frequency of the processing, and the timing of the processing (variation of the frequency of the processing), etc. of the respective manufacturing equipments EQ1A to EQnA and EQ1B to EqnB, it is possible to reduce the lot standby time of the manufacturing equipments EQ1A to EQnA and that of the manufacturing equipments EQ1B to EQnB, and therefore to reduce the TAT of the products manufactured in the semiconductor manufacturing line in the fourth embodiment.

[0084] Note that, in the fourth embodiment, the example, in which the three RGVs are arranged on the transfer rail 3 and the stockers of the same number as the RGVs are arranged in the region being along the transfer rail 3, has been described. However, the number of the RGVs is not limited to three, and it is also possible to arrange the further more number of RGVs and to arrange the number of stockers proportional to the further more number thereof.

[0085] The same effect as that of the second embodiment can be achieved in the fourth embodiment as described above.

[0086] In the foregoing, the invention made by the inventors has been concretely described based on the embodiments. However, needless to say, the present invention is not limited to the foregoing embodiments and can be variously modified and altered without departing from the scope thereof.

[0087] Also, in the foregoing embodiments, there has been described the case where the present invention is applied to the transfer system for the wafer lot in the semiconductor manufacturing line. However, it is also possible to apply the present invention to a transfer system other than the semiconductor manufacturing line, for example, to the transfer system in the manufacturing line of a liquid crystal display.

[0088] The advantages achieved by the typical ones of the inventions disclosed in this application will be briefly described as follows.

[0089] (1) Even when the transfer rail (single track) is blocked, the objects to be transferred can be transferred to the manufacturing equipments (including test equipments) provided in the region (second region) other than the blocked region (first region) and, therefore, the reduction in operation rate of the manufacturing equipments can be prevented.

[0090] (2) Since a plurality of RGVs (transfer means) are arranged on the transfer rail (single track) and the respective transfer regions (second transfer regions) of the RGVs are newly set based on the respective operation rates of the RGVs, it is possible to equalize the operation rate of each RGV and that of each manufacturing equipment (including test equipments) to which the objects to be transferred are carried by the RGVs. 

What is claimed is:
 1. A transfer method comprising the steps of: using a single track connecting a plurality of manufacturing equipments, and a plurality of transfer means operating along said single track; and transferring, to said manufacturing equipments, an object to be transferred, wherein each of said transfer means has a transfer mode of a first step and a second step after said first step, and a first transfer region of each of said transfer means at said first step and a second transfer region of each of said second transfer means at said second step are different from each other in range.
 2. The transfer method according to claim 1, wherein said first transfer region and said second transfer region of one of said plurality of transfer means are mutually separated from said first transfer region and said second transfer region of the other of said transfer means.
 3. The transfer method according to claim 1, wherein said transfer means are RGVs moving on or along said single track.
 4. The transfer method according to claim 1, wherein said object to be transferred is a semiconductor wafer lot with a diameter of 300 mm or larger.
 5. A transfer method comprising the steps of: using a single track connecting a plurality of manufacturing equipments, and a plurality of transfer means operating along said single track; and transferring, to said manufacturing equipments, an object to be transferred, wherein at least one of said transfer means has a transfer mode of a first step and a second step being at the time of blocking off said single track, and a first transfer region of said at least one of the transfer means at said first step and a second transfer region of said at least one of the transfer means at said second step are different from each other in range.
 6. The transfer method according to claim 5, wherein said first transfer region and said second transfer region of the one of said plurality of transfer means are mutually separated from said first transfer region and said second transfer region of the other of said transfer means.
 7. The transfer method according to claim 5, wherein while doing maintenance of said manufacturing equipments or making a new or additional installation of at least one of said manufacturing equipments, said single track is blocked at a position of said maintenance or said new or additional installation.
 8. The transfer method according to claim 5, wherein said transfer means are RGVs moving on or along said single track.
 9. The transfer method according to claim 5, wherein said object to be transferred is a semiconductor wafer lot with a diameter of 300 mm or larger.
 10. A transfer method comprising the steps of: using a single track connecting a plurality of manufacturing equipments, and a plurality of transfer means operating along said single track; and transferring, to said manufacturing equipments, an object to be transferred, wherein each of said transfer means has a transfer mode of a first step being at which a difference in operation rate occurs between said plurality of transfer means and a second step at which said difference in the operation rate is smaller than that at said first step, and a first transfer region of each of said transfer means at said first step and a second transfer region of each of said transfer means at said second step are different from each other in range.
 11. The transfer method according to claim 10, wherein said first transfer region and said second transfer region of one of said plurality of transfer means are mutually separated from said first transfer region and said second transfer region of the other of said transfer means.
 12. The transfer method according to claim 10, wherein said second transfer region of each of said transfer means at the second step is set based on a processing time, frequency of the processing, and timing of the processing of said plurality of manufacturing equipments at said first step.
 13. The transfer method according to claim 10, wherein said transfer means are RGVs moving on or along said single track.
 14. The transfer method according to claim 10, wherein said object to be transferred is a semiconductor wafer lot with a diameter of 300 mm or larger.
 15. A transfer method comprising the steps of: using a single track connecting a plurality of manufacturing equipments, and a plurality of transfer means operating along said single track; and transferring, to said manufacturing equipments, an object to be transferred, wherein each of said transfer means has a transfer mode of a first step at which there occurs a difference in the standby time until said object to be transferred is transferred to said plurality of manufacturing equipments and a second step at which said difference in the standby time is smaller than that at said first step, and a first transfer region of each of said transfer means at said first step and a second transfer region of each of said transfer means at said second step are different from each other in range.
 16. The transfer method according to claim 15, wherein said first transfer region and said second transfer region of one of said plurality of transfer means are mutually separated from said first transfer region and said second transfer region of the other of said transfer means.
 17. The transfer method according to claim 15, wherein said second transfer region of each of said transfer means at said second step is set based on a processing time, frequency of the processing, and timing of the processing of each of said plurality of manufacturing equipments at said first step.
 18. The transfer method according to claim 15, wherein said transfer means are RGVs moving on or along said single track.
 19. The transfer method according to claim 15, wherein said object to be transferred is a semiconductor wafer lot with a diameter of 300 mm or larger. 